SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

Ms. Julie Myrah - 2 - • 14 September 2006 Mr. Mike Desso j potable water could violate the new permit and management plan, both currently in draft form. Ms. Myrah indicated that it was her understanding that the draft Statewide NPDES permit might be finalized in August. Allan Shafer, Caltrans maintenance storm water coordinator indicated that the revised draft Statewide SWMP did not conditionally exempt the discharge of non-potable,water when used for landscape irrigation. Martin Keck of Caltrans legal staff summarized Caltrans position on the use of the non- potable water. It appears to be a low-risk issue for Caltrans, but Caltrans wants a letter `rom Regional Water Board staff that supports the use of the City of Ripon's non-potable water and indicates that this action will not violate the conditions of the future Statewide Storm Water permit, currently in draft form. The Regional Water Board supports appropriate uses of non-potable water. However, we cannot unequivocally state that use of non-potable water will not violate future storm water permit conditions due to variables not under our control. Storm water discharge by the City of Ripon is regulated under State Water Resources Control Board Water Quality Order No. 2003-0005-DWQ, NPDES General Permit No. CAS000004, Waste Discharge Requirements for Storm Water Discharges From Small Municipal Separate Storm Sewer Systems (General Small MS4 permit) and must comply with their SWMP issued in 2003. The water sources for Ripon's non-potable water system are groundwater from city wells that do not meet drinking water standards (apparently due primarily to nitrate concentrations) and treated groundwater from two Nestle remediation systems. According to Matt Machado, Ripon City Engineer, the non-potable system delivers water for irrigation to all major parks, commercial areas, industrial areas, and new residential subdivisions under construction. The use of non-potable water for irrigation of parks and residential landscaping within the City of Ripon likely results in incidental runoff to the city's storm sewer system. This runoff is considered a non-storm water discharge under the General Small MS4 permit. Discharge of non-potable water to the city's storm sewer system may be allowable under that permit. However, the Regional Water Board will be working with the city of Ripon to gain more information on its non-potable system, and potential runoff of the water to its storm sewer system. Discharge of non-potable water runoff is not currently addressed in the Ripon SWMP. The new Caltrans Statewide Storm Water Permit and associated SWMP are still in the development process. Once finalized, the Permit and SWMP must go through public review and comment prior to consideration for adoption by the State Water Resources Control Board. Although revisions to the Permit and SWMP will occur as a result of this process, we anticipate that the use of non-potable water for irrigation purposes will continue to be encouraged. For questions regarding compliance with the Caltrans Statewide Storm Water permit, please contact Dannas Berchtold of the Regional Water Board's Storm Water Unit at (916) 464-4683, or by email at dberchtold@waterboards.ca.gov. For questions regarding compliance with the City of Ripon's General Small MS4 permit, please contact Kim Schwab also of the Regional Water Board's Storm Water Unit at (916) 464-4606. If Nestle and Caltrans cannot reach agreement on use of non-potable water on a permanent basis, they should consider alternatives such as well-head treatment. Well-head treatment could be used as a temporary solution until a permanent solution is agreed upon.